Aluminum A356.2
AA A356.2 · ASTM B26/B108 · EN AlSi7Mg0.3
A356.2 is the low-impurity ingot grade of the Al-7Si-Mg casting alloy A356, cast to the B26 (sand) and B108 (permanent-mould) specification family, with tight Mg control and low Fe for maximum ductility and fatigue life.
Values for the T6 condition
A356.2 tempers and conditions
A356.2 is supplied in 6 conditions, soft to hard. T6 is the default FabDigit quotes; the values on this page are for it.
Compare all 6 conditionsHide
| Condition · open for datasheet | Best for | Yield MPa | Tensile MPa | Elong. % | Hardness | Conductivity |
|---|---|---|---|---|---|---|
As fabricated | Pick for low-stress, dimensionally sensitive castings where heat-treat distortion or cost is unacceptable. | 83 | 159 | 6 | 55 HB | 39 % IACS |
T5, stress relieved by stretching | Low-cost temper for stability and modest strength gain without the distortion of solution quenching. | 138 | 172 | 2 | 60 HB | 41 % IACS |
Solution heat treated and fully overaged for maximum stability | Softest heat-treated condition; picked for best machinability, minimum residual stress and long-term thermal stability. | 145 | 207 | 3 | 65 HB | 43 % IACS |
T6Default Solution heat treated and artificially aged | Default structural temper: best balance of strength, ductility and fatigue life for wheels, knuckles and housings. | 186 | 262 | 5 | 80 HB | 40 % IACS |
Solution heat treated and overaged (stabilized) | Use where dimensional stability at elevated temperature and reduced residual stress matter more than peak strength. | 200 | 234 | 3 | 75 HB | 42 % IACS |
T6 variant, underaged | Choose when maximum strength and hardness are needed from permanent-mold castings and some ductility loss is acceptable. | 207 | 283 | 6 | 90 HB | 40 % IACS |
What is A356.2?
A356.2 is the low-impurity ingot grade of the Al-7Si-Mg casting alloy A356, cast to the B26 (sand) and B108 (permanent-mould) specification family, with tight Mg control and low Fe for maximum ductility and fatigue life. Engineers specify it for aerospace and other safety-critical castings produced by sand, permanent-mould, low-pressure and investment routes; in T6 it gives 186 MPa yield, 262 MPa tensile, 5 % elongation and 80 HB. Thermal conductivity is 151 W/m·K, electrical conductivity 40 % IACS, and service temperature is limited to about 150 °C. Standard A356.0/A356.1 is cheaper where the tighter impurity limits are not required. A356.2 has a density of 2.68 g/cm³ (0.0968 lb/in³), lighter than 72% of aluminum grades. It melts at 557°C (1,035 °F). A356.2 has a yield strength of 186 MPa (27 ksi) and a tensile strength of 262 MPa (38 ksi) — weaker than 52% of aluminum grades. Elongation at break is 5% and the elastic modulus is 72.4 GPa (10.5 Msi).
What is A356.2 used for?
- Aerospace castings
- Aircraft wheels
- Gearbox and accessory housings
- Structural airframe brackets
- Pump and valve bodies
- Automotive suspension components
- Cast road wheels
Limitations
- Limited formability — 10/100, worse than 80% of aluminum grades
A356.2 properties
Typical room-temperature values for A356.2-T6; bars are the position among aluminum grades.
Physical3
A356.2 has a density of 2.68 g/cm³ (0.0968 lb/in³), lighter than 72% of aluminum grades. It melts at 557°C (1,035 °F).
Mechanical12
A356.2 has a yield strength of 186 MPa (27 ksi) and a tensile strength of 262 MPa (38 ksi) — weaker than 52% of aluminum grades. Elongation at break is 5% and the elastic modulus is 72.4 GPa (10.5 Msi).
Thermal6
A356.2 is rated for continuous service to 150°C (302 °F). It conducts heat at 151 W/m·K (87.2 BTU/hr·ft·°F), better than 63% of aluminum grades. Thermal expansion is 21.5 µm/m·K (11.9 µin/in·°F).
Electrical3
A356.2 conducts electricity at 40 % IACS, better than 72% of aluminum grades.
Chemical & Environmental3
Corrosion resistance is good (65/100), better than 71% of aluminum grades.
Sustainability4
Producing a kilogram of A356.2 takes about 195 MJ of energy and emits 12 kg of CO₂ — less than 86% of aluminum grades. Typical recycled content is 10%.
Manufacturability8
A356.2's machinability is good (62/100, better than 55% of aluminum grades); weldability very good (80/100); formability not recommended (10/100).
Common Calculations5
Values are nominal handbook figures for design screening. Certified mill or lot data ships with every FabDigit order on request.
Strength versus weight in the aluminum family
Yield strength against density for every aluminum grade FabDigit runs. A356.2 is highlighted; hover a dot for its name, or open the interactive family chart.
Working with A356.2
Is A356.2 easy to machine?
Machines cleanly in T6 with polished-flute carbide or PCD tooling and high speed; eutectic Si is abrasive so avoid HSS for production runs.
Can A356.2 be welded?
Readily TIG/MIG welded or repaired with 4043/4145 filler; re-solution and re-age welded structural castings to restore T6 properties.
Can A356.2 be formed, bent or molded?
Excellent fluidity and low hot-tearing for sand, permanent-mold, low-pressure and investment casting; Sr modification plus Ti-B refinement and directional solidification are needed for high-elongation T6 parts.
Manufacturability
The process limits FabDigit applies to A356.2. Every A356.2 part is priced by an engineer; design inside these and the quote comes back without a redesign loop.
CNC machining
| Machinability | Good62 / 100 |
|---|---|
| ISO material group | N.1 |
| Cutting speed (rough / finish) | 350 / 420 m/min |
| Minimum wall | 0.5 mm |
| Minimum internal radius | 1 mm |
| Drill depth limit | 8× diameter |
| Best surface (machined / polished) | Ra 0.8 / — |
| Hardenable after machining | No |
A356.2 chemical composition (wt %)
Limits by weight percent from the governing specification, written the way the spec states them — a single maximum for impurities, a range for alloying elements, and the base element as balance. Nominal is the typical mid-range value.
| Element | Spec limit (wt %) | Nominal |
|---|---|---|
| Si | 6.5 – 7.5 | 7 |
| Mgaging element; Sr/Na modification typical | 0.3 – 0.45 | 0.35 |
| Fetight Fe limit distinguishes A356.2 from 356.2 | ≤ 0.12 | 0.08 |
| Cu | ≤ 0.1 | |
| Mn | ≤ 0.05 | |
| Zn | ≤ 0.05 | |
| Tigrain refinement, usually with B | ≤ 0.2 | 0.12 |
| Others (each) | ≤ 0.05 | |
| Others (total) | ≤ 0.15 | |
| Al | balance |
What surface finishes work on A356.2?
Takes hardcoat anodize and chromate/paint well but decorative sulfuric anodize turns grey; shot peening is common to raise fatigue life.
Surface treatments FabDigit runs on aluminum parts — pick them in the quote configurator or call them out on the drawing. Each links to its datasheet in the surface-finish library (thickness, specs, call-out, material verdicts).
Passivation
Conversion Coating
PVD Coating
Equivalent designations
Standards and trade names that resolve to Aluminum A356.2 in FabDigit's catalog. Equivalence is nominal — check the exact specification when certification matters.
- ASTM
- B26/B108
- EN / DIN / Werkstoff-Nr.
- AlSi7Mg0.3
How much does A356.2 cost?
A356.2 is a premium-cost aluminum ($$$), cheaper than about 60% of the materials FabDigit quotes. Part price depends far more on geometry, tolerance and quantity than on the raw stock — upload a CAD file for a live quote.
A356.2 — frequently asked
What is A356.2 used for?
A356.2 is typically used for aerospace castings, aircraft wheels, gearbox and accessory housings, structural airframe brackets, pump and valve bodies and automotive suspension components. In short: aerospace-spec A356; tight Mg/Fe control; heat-treatable.
What is the yield strength of A356.2?
A356.2 has a typical yield strength of 186 MPa (27 ksi) and a tensile strength of 262 MPa (38 ksi) — weaker than 52% of aluminum grades. Strength varies by condition: see the 6 listed tempers.
Is A356.2 easy to machine?
Reasonably — machinability is rated good (62/100, better than 55% of aluminum grades). Machines cleanly in T6 with polished-flute carbide or PCD tooling and high speed; eutectic Si is abrasive so avoid HSS for production runs.
Can A356.2 be welded?
Yes — weldability is rated very good (80/100). Readily TIG/MIG welded or repaired with 4043/4145 filler; re-solution and re-age welded structural castings to restore T6 properties.
What surface finishes work on A356.2?
Takes hardcoat anodize and chromate/paint well but decorative sulfuric anodize turns grey; shot peening is common to raise fatigue life.
Can A356.2 be formed, bent or molded?
Excellent fluidity and low hot-tearing for sand, permanent-mold, low-pressure and investment casting; Sr modification plus Ti-B refinement and directional solidification are needed for high-elongation T6 parts.
What is the maximum service temperature of A356.2?
A356.2 is rated for continuous use to about 150°C (302 °F). Strength falls off well before that limit — check the elevated-temperature data for load-bearing parts.
What is the difference between A356.2-T6 and A356.2-F?
T6 is the default condition — default structural temper: best balance of strength, ductility and fatigue life for wheels, knuckles and housings. F: pick for low-stress, dimensionally sensitive castings where heat-treat distortion or cost is unacceptable. Yield strength is 186 MPa in T6 versus 83 MPa in F.
How much does A356.2 cost?
A356.2 is a premium-cost aluminum ($$$), cheaper than about 60% of the materials FabDigit quotes. Part price depends far more on geometry, tolerance and quantity than on the raw stock — upload a CAD file for a live quote.
Can FabDigit make parts in A356.2?
Yes — A356.2 is available for CNC machining; every part is priced by an engineer rather than instantly. Upload a STEP file to get a price and a DFM check.
Sources
- ASTM B179 — Aluminum Alloys in Ingot and Molten Forms for Castings — ASTM International (2022)
- ASTM B26/B26M and B108/B108M — Aluminum-Alloy Sand and Permanent Mold Castings — ASTM International (2022)
- ASM Handbook Vol. 2 — Properties and Selection: Nonferrous Alloys — ASM International (1990)
- Aluminum Association Registration Records (Teal Sheets / Pink Sheets) — The Aluminum Association (2018)
- GB/T 1173 (ZL101A ) — SAC (2013)
Property data is compiled from published supplier and standards handbooks and normalised for comparison; hardness values on non-Brinell scales are converted approximately for charting only. Manufacturability limits are FabDigit quote-engine defaults and may be relaxed by engineering review. Nothing on this page is a certification — request mill certs, CoC or material test reports with your order.